[XFS] Start writeout earlier (on last close) in the case where we have a
truncate down followed by delayed allocation (buffered writes) - worst
case scenario for the notorious NULL files problem. This reduces the
window where we are exposed to that problem significantly.
SGI-PV: 917976
SGI-Modid: xfs-linux-melb:xfs-kern:26100a
Signed-off-by: Nathan Scott <nathans@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_vnode.h b/fs/xfs/linux-2.6/xfs_vnode.h
index a64b7db..569a4e7 100644
--- a/fs/xfs/linux-2.6/xfs_vnode.h
+++ b/fs/xfs/linux-2.6/xfs_vnode.h
@@ -56,12 +56,18 @@
typedef struct dentry vname_t;
typedef bhv_head_t vn_bhv_head_t;
+typedef enum vflags {
+ VMODIFIED = 0x08, /* XFS inode state possibly differs */
+ /* to the Linux inode state. */
+ VTRUNCATED = 0x40, /* truncated down so flush-on-close */
+} vflags_t;
+
/*
* MP locking protocols:
* v_flag, v_vfsp VN_LOCK/VN_UNLOCK
*/
typedef struct vnode {
- __u32 v_flag; /* vnode flags (see below) */
+ vflags_t v_flag; /* vnode flags (see above) */
struct vfs *v_vfsp; /* ptr to containing VFS */
vnumber_t v_number; /* in-core vnode number */
vn_bhv_head_t v_bh; /* behavior head */
@@ -126,12 +132,6 @@
}
/*
- * Vnode flags.
- */
-#define VMODIFIED 0x8 /* XFS inode state possibly differs */
- /* to the Linux inode state. */
-
-/*
* Values for the VOP_RWLOCK and VOP_RWUNLOCK flags parameter.
*/
typedef enum vrwlock {
@@ -162,8 +162,10 @@
VCHANGE_FLAGS_IOEXCL_COUNT = 4
} vchange_t;
+typedef enum { L_FALSE, L_TRUE } lastclose_t;
typedef int (*vop_open_t)(bhv_desc_t *, struct cred *);
+typedef int (*vop_close_t)(bhv_desc_t *, int, lastclose_t, struct cred *);
typedef ssize_t (*vop_read_t)(bhv_desc_t *, struct kiocb *,
const struct iovec *, unsigned int,
loff_t *, int, struct cred *);
@@ -234,6 +236,7 @@
typedef struct vnodeops {
bhv_position_t vn_position; /* position within behavior chain */
vop_open_t vop_open;
+ vop_close_t vop_close;
vop_read_t vop_read;
vop_write_t vop_write;
vop_sendfile_t vop_sendfile;
@@ -278,6 +281,10 @@
*/
#define _VOP_(op, vp) (*((vnodeops_t *)(vp)->v_fops)->op)
+#define VOP_OPEN(vp, cr, rv) \
+ rv = _VOP_(vop_open, vp)((vp)->v_fbhv, cr)
+#define VOP_CLOSE(vp, f, last, cr, rv) \
+ rv = _VOP_(vop_close, vp)((vp)->v_fbhv, f, last, cr)
#define VOP_READ(vp,file,iov,segs,offset,ioflags,cr,rv) \
rv = _VOP_(vop_read, vp)((vp)->v_fbhv,file,iov,segs,offset,ioflags,cr)
#define VOP_WRITE(vp,file,iov,segs,offset,ioflags,cr,rv) \
@@ -290,8 +297,6 @@
rv = _VOP_(vop_splice_write, vp)((vp)->v_fbhv,f,o,pipe,cnt,fl,iofl,cr)
#define VOP_BMAP(vp,of,sz,rw,b,n,rv) \
rv = _VOP_(vop_bmap, vp)((vp)->v_fbhv,of,sz,rw,b,n)
-#define VOP_OPEN(vp, cr, rv) \
- rv = _VOP_(vop_open, vp)((vp)->v_fbhv, cr)
#define VOP_GETATTR(vp, vap, f, cr, rv) \
rv = _VOP_(vop_getattr, vp)((vp)->v_fbhv, vap, f, cr)
#define VOP_SETATTR(vp, vap, f, cr, rv) \
@@ -556,8 +561,6 @@
*/
#define VN_LOCK(vp) mutex_spinlock(&(vp)->v_lock)
#define VN_UNLOCK(vp, s) mutex_spinunlock(&(vp)->v_lock, s)
-#define VN_FLAGSET(vp,b) vn_flagset(vp,b)
-#define VN_FLAGCLR(vp,b) vn_flagclr(vp,b)
static __inline__ void vn_flagset(struct vnode *vp, uint flag)
{
@@ -566,13 +569,22 @@
spin_unlock(&vp->v_lock);
}
-static __inline__ void vn_flagclr(struct vnode *vp, uint flag)
+static __inline__ uint vn_flagclr(struct vnode *vp, uint flag)
{
+ uint cleared;
+
spin_lock(&vp->v_lock);
+ cleared = (vp->v_flag & flag);
vp->v_flag &= ~flag;
spin_unlock(&vp->v_lock);
+ return cleared;
}
+#define VMODIFY(vp) vn_flagset(vp, VMODIFIED)
+#define VUNMODIFY(vp) vn_flagclr(vp, VMODIFIED)
+#define VTRUNCATE(vp) vn_flagset(vp, VTRUNCATED)
+#define VUNTRUNCATE(vp) vn_flagclr(vp, VTRUNCATED)
+
/*
* Dealing with bad inodes
*/
@@ -612,8 +624,7 @@
#define VN_CACHED(vp) (vn_to_inode(vp)->i_mapping->nrpages)
#define VN_DIRTY(vp) mapping_tagged(vn_to_inode(vp)->i_mapping, \
PAGECACHE_TAG_DIRTY)
-#define VMODIFY(vp) VN_FLAGSET(vp, VMODIFIED)
-#define VUNMODIFY(vp) VN_FLAGCLR(vp, VMODIFIED)
+#define VN_TRUNC(vp) ((vp)->v_flag & VTRUNCATED)
/*
* Flags to VOP_SETATTR/VOP_GETATTR.